Bookmakers were toasting the 66/1 success of Auroras Encore in Saturday's John Smith's Grand National at Aintree.

A sustained day-of-race gamble sent Katie Walsh and Seabass off as 11/2 favourites but they could only finish 13th as the Sue Smith-trained winner stormed home nine lengths clear of Cappa Bleu (12/1), Teaforthree (10/1) and Oscar Time (66/1).

Sky Bet spokesman Michael Shinners said: "Without doubt it was a tremendous result for us. It wasn't looking great when Teaforthree led going to the last. However, when the best result in the book Auroras Encore shot clear, Sky Bet towers erupted.

"More importantly 40 horses and jockeys returned safe and sound following the 2013 John Smith's Grand National."

Kate Miller, spokeswoman for William Hill, admitted: "We couldn't have written a better result. Punters were out in their droves to support this fantastic British sporting tradition - it's popularity cannot be in question, and hardly any of them found the winner Auroras Encore.

"It's a great result for racing, a great result for sport, and an even better result for William Hill shareholders!'"

Aintree's official betting partner Betfred were staring at £2million loss had Seabass won - and £1million if Teaforthree had prevailed.

A relieved and jubilant Fred Done said: "It was a grand result as we avoided a national gamble on Seabass that would have cost the industry more than a drop in the ocean."

David Williams, of Ladbrokes, added: "It was a result beyond our wildest dreams. The winner seemed to slip off every radar. We thought Mon Mome's victory a few years ago was superb but this was every bit as good.

"Turnover went through the roof as the nation came out for its annual flutter. The race is once again in rude health and the sun shone on the bookies at Aintree."

Stan James were another firm to fear the worst when Teaforthree set sail for home and Rory Jiwani said: "There were more then a few nerves shredded in the office as Teaforthree moved ominously into contention. He and Imperial Commander were the only big losers in our book but 66/1 shot Auroras Encore swept past under Ryan Mania to the delight of us bookies.

"Many congratulations to Sue and Harvey Smith on training a Grand National winner but the best news of all is that there were no injuries to horses or jockeys. It was a superb race which will hopefully allay fears about the future of the National."